source/stereoview.cpp

   1 #include <msp/gl/renderer.h>
   2 #include "headtrackingcamera.h"
   3 #include "stereocombiner.h"
   4 #include "stereoview.h"
   5
   6 using namespace std;
   7
   8 namespace Msp {
   9 namespace VR {
  10
  11 StereoView::StereoView(const StereoCombiner &c, const GL::Camera &a):
  12         combiner(c),
  13         base_camera(a),
  14         head_camera(0)
  15 {
  16         init();
  17 }
  18
  19 StereoView::StereoView(const StereoCombiner &c, HeadTrackingCamera &a):
  20         combiner(c),
  21         base_camera(a),
  22         head_camera(&a)
  23 {
  24         init();
  25 }
  26
  27 void StereoView::init()
  28 {
  29         content = 0;
  30
  31         unsigned w = combiner.get_target_width();
  32         unsigned h = combiner.get_target_height();
  33         left.create_target(w, h);
  34         right.create_target(w, h);
  35
  36         set_eye_spacing(0.064);
  37         set_strabismus(Geometry::Angle<float>::zero());
  38 }
  39
  40 void StereoView::set_content(const GL::Renderable *r)
  41 {
  42         content = r;
  43 }
  44
  45 void StereoView::set_eye_spacing(float s)
  46 {
  47         GL::Vector3 offset(s/2, 0, 0);
  48         set_eye_matrices(GL::Matrix::translation(-offset), GL::Matrix::translation(offset));
  49 }
  50
  51 void StereoView::set_eye_matrices(const GL::Matrix &left_matrix, const GL::Matrix &right_matrix)
  52 {
  53         left.offset_matrix = left_matrix;
  54         right.offset_matrix = right_matrix;
  55 }
  56
  57 void StereoView::set_strabismus(const Geometry::Angle<float> &s)
  58 {
  59         strabismus = s;
  60 }
  61
  62 void StereoView::setup_frame() const
  63 {
  64         if(head_camera)
  65                 head_camera->update();
  66
  67         EyeParams params;
  68         params.fov = combiner.get_field_of_view();
  69         if(params.fov==Geometry::Angle<float>::zero())
  70                 params.fov = base_camera.get_field_of_view();
  71
  72         params.aspect = combiner.get_render_aspect();
  73         params.near_clip = base_camera.get_near_clip();
  74         params.far_clip = base_camera.get_far_clip();
  75
  76         float frustum_skew = combiner.get_frustum_skew();
  77         float halfw = tan(params.fov/2.0f)*params.aspect;
  78         frustum_skew = tan(Geometry::atan<float>(frustum_skew*halfw)+strabismus)/halfw;
  79
  80         left.setup_frame(base_camera, frustum_skew, params);
  81         right.setup_frame(base_camera, -frustum_skew, params);
  82 }
  83
  84 void StereoView::render() const
  85 {
  86         combiner.prepare();
  87         setup_frame();
  88         if(content)
  89         {
  90                 content->setup_frame();
  91                 left.render(*content);
  92                 right.render(*content);
  93                 content->finish_frame();
  94         }
  95         combiner.render(left.target->color, right.target->color);
  96 }
  97
  98
  99 StereoView::RenderTarget::RenderTarget(unsigned width, unsigned height)
 100 {
 101         color.set_min_filter(GL::LINEAR);
 102         color.set_wrap(GL::CLAMP_TO_EDGE);
 103         color.storage(GL::RGB, width, height);
 104         fbo.attach(GL::COLOR_ATTACHMENT0, color);
 105
 106         depth.storage(GL::DEPTH_COMPONENT, width, height);
 107         fbo.attach(GL::DEPTH_ATTACHMENT, depth);
 108 }
 109
 110
 111 StereoView::Eye::Eye():
 112         target(0)
 113 { }
 114
 115 void StereoView::Eye::create_target(unsigned w, unsigned h)
 116 {
 117         delete target;
 118         target = new RenderTarget(w, h);
 119 }
 120
 121 void StereoView::Eye::setup_frame(const GL::Camera &base_camera, float frustum_skew, const EyeParams &params) const
 122 {
 123         GL::Matrix matrix = base_camera.get_object_matrix()*offset_matrix;
 124         camera.set_position(matrix*GL::Vector3());
 125         camera.set_up_direction((matrix*GL::Vector4(0, 1, 0, 0)).slice<3>(0));
 126         camera.set_look_direction((matrix*GL::Vector4(0, 0, -1, 0)).slice<3>(0));
 127
 128         camera.set_field_of_view(params.fov);
 129         camera.set_aspect(params.aspect);
 130         camera.set_depth_clip(params.near_clip, params.far_clip);
 131         camera.set_frustum_axis(frustum_skew, 0);
 132 }
 133
 134 void StereoView::Eye::render(const GL::Renderable &renderable) const
 135 {
 136         GL::Bind bind_fbo(target->fbo);
 137         target->fbo.clear(GL::COLOR_BUFFER_BIT|GL::DEPTH_BUFFER_BIT);
 138         GL::Renderer renderer(&camera);
 139         renderable.render(renderer);
 140 }
 141
 142 } // namespace VR
 143 } // namespace Msp